(semi-leading question:)
Why keep using wormholes? The Nomad planets system suggests that it is possible to create and destroy wormhole links - was there any attempts to discover how to make them, other methods of "FTL", etc. - if so, how did they (spectacularly) fail?
(Zenith/Spire lore:)
If Spire factions are involved in recreating Zenith machines and/or actual Zenith beings (if those ships are indeed individual Zenith like the Spires are partially their ships), I'm presuming that relationship between the two are somewhat complicated - how do they feel about each other: slavemaster/liberator/troublemaker/...? Do the Zenith go out, contact the remaining golems, and try to rediscover their lost culture, and/or do they forge their own?
(human/Zenith lore:)
Those Zenith TraitorsTraders - how many of them are there? Where are they now (hopefully they did not end up like the Brady Bunch)?
(Pure human lore:)
At the end of AI War Classic, were the surviving humans mostly in the cryopods and ships (the AI having destroyed surface civilisations), or were there still significant inhabited worlds around? What kinds of divisions have split humanity in the sequel?
(Multi-species culture:)
Do you envisage any significant cities/settlements/colonies where more than one civilisation are sharing the same space peacefully? E.g. would there be a mixed race minor/backgrounf faction?